Lego games are designed for players of all ages, and as such, they do not feature any violence or death. Instead of killing enemies, you will typically knock them out or incapacitate them in some way.
If you are looking for a game with a more violent or mature theme, Lego Batman 2 is probably not the right choice for you. However, it is a fun and entertaining game with a lot of humor and action, perfect for players of all ages.